REMAINING (number with state)Abdomen, T2 and T3, position of distinct, light-colored, hair bands near the rim of the segment, if present Band of hairs significantly set back from apical rim, especially so in the center (21) Hair bands ABSENT, may possess lateral patches of dense, plumose hairs (8) Band of hairs set right ON the rim (3)Abdomen, T2, color of interband hair - The often sparse hairs that lie between the band of white on or near the rim and the band of white hair that usually follows the base of the segment and is sometimes partially hidden by the overlap with the preceding abdominal segment All or partly DARK (21) All LIGHT (18)Abdomen, T4, color of thickened, sub-erect hairs present just behind or in the back edge of the distinct, light-colored hair band of hairs that lies just behind or on the rim of the segment - These hairs are much longer and sparser than those in the hair band and are most easily seen from the side Light, white to golden blond (22) Black (16) Mixed light and dark (15)EXPERIENCED USERS - Head, galaea, appearance of basal 2/3 of the top surface - Look carefully on high magnification Shiny, surface smooth except for few a sparse pits bearing short hairs (21) Slightly to moderately roughened or scaly, as if covered by a thin, fine, reptilian skin (15)Head, antennae, shortest length of 1st flagellar segment vs length of pedicel Less than or equal to (24) Clearly greater than (16)Head, cheek, hair color All LIGHT (26) All dark or with 30 percent or more dark hairs (2)Head, clypeus, color Entirely yellow or off-white, may be narrowly outlined in black around margin and tentorial pits (27) Black with some patches of yellow or off-white (6) Entirely black (1)Head, labrum, color Black with a patch of yellow or off-white (19) Entirely yellow, may be narrowly outlined in black or brown (16) Entirely black or brown (14)Head, mandibles, color Black with gold on APEX only (18) Black with yellow on BASE and gold on APEX (16) Entirely black (4) Black with yellow on BASE only (3)Head, vertex, color of hair - These hairs include those on the actual vertex and those that may be coming up from underneath the back of the head All LIGHT (27) Both dark and light hairs (7) All DARK (1)M. agilis vs. M. nivea M. agilis - Head, antennae, 1st flagellar segment length compared to pedicel length, GREATER, but not by much - Overall color, a slightly rustier bee in comparison (1) M. nivea - Head, antennae, 1st flagellar segment length compared to pedicel length, clearly LESS, but not by much - Overall color, a very bright white looking bee in comparison (1)M. agilis vs. M. tepaneca M. agilis - Head, labrum, OUTLINED on the sides in brown or black - Galaea, basal two-thirds with a faint network of lines visible usually only at high magnification (1) M. tepaneca - Head, labrum, COMPLETELY YELLOW - Galaea, basal two-thirds SMOOTH with only scattered pits (1)M. agilis vs. M. trinodis - FRESH SPECIMENS - Note that hair and tergites rims in old M. trinodis will fade to white and will be very hard to distinguish from M. agilis M. agilis - Abdomen, tergite rims, almost completely CLEAR - Head, mandible base, with a clear YELLOW MARK - Forewing, vein color, a light YELLOW - Thorax, scutum, general color of hairs, OFF-WHITE (1) M. trinodis - Abdomen, tergite rims, transparent, but infused with a dark brown - Head, mandible base, often ENTIRELY DARK, but can CAN ALSO HAVE have a yellow patch - Forewings, vein color, light to dark brown - Thorax, scutum, general color of hairs, can AT TIMES be infused with rust or dark orange (1)M. agilis vs. M. wheeleri M. agilis - Thorax and abdomen, all hairs ENTIRELY PALE (1) M. wheeleri - Thorax, scutum and scutellum, with extensive amounts of DARK to LIGHT brown to black hairs - Abdomen, T5 and behind the transverse white hair bands on T2-4, with extensive amounts of DARK to LIGHT brown to black hairs (1)M. boltoniae vs. M. fumosa - NOTE - The males of these two species are currently not thought to be separable without a long series of each - See explain for details M. boltoniae (1) M. fumosa (1)M. communis vs. M. comptoides vs. M. tepaneca M. communis - Often confused with M. comptoides - Head, antennae, the short side of the first flagellar segment CLEARLY longer than the pedicel - Scutum, central rear third, many pits greater than 1 pit diameter apart - T5 apical hair band black with possibly a few white hairs at the far lateral sides - Literature mentions that this species is told from M. tepaneca by darker wings and the presence of rusty hairs on the thorax - Very difficult at times to separate the three species (1) M. comptoides - Head, antennae, the short side of the first flagellar usually a tiny bit longer than the pedicel, much less so than in M. communis - Abdomen, scutum, central rear third, pitting is uniform and almost always less than 1 pit diameter apart - T5, apical hair band black - In direct comparison with M. communis, the rim area of T2 has a higher density of pits (1) M. tepaneca - Abdomen, T2, interband hair LIGHT, or at times with some black - T5, apical hair band WHITE, at least in part - Literature mentions that this species is told from M. communis by clear, uncolored wings and off-white hair on the thorax - Very difficult to separate the two species (1)M. communis vs. M. menuachus vs. M. nivea M. communis - Head, antennae, length of F1 may in some individuals appear to be equal to the length of the pedicel, but in most it will be longer - Labrum, appears to always be completely YELLOW - Mandible base, almost completely YELLOW - Abdomen, T5 and T6, hairs, either all BLACK or mostly black - Wings, outer sections TINTED with a bit of light brown (1) M. menuachus - Head, antennae, length of F1 may in some individuals appear to be equal to the length of the pedicel, but in most it will be longer - Mandible base, with a prominent YELLOW SPOT - Labrum, with yellow in the center and dark on the outer edges - Abdomen, T5 and T6, hairs, all WHITE - Wings, without any dark tinting (1) M. nivea - Head, antennae, length of F1 clearly LESS THAN the pedicel - Labrum with yellow in the center dark on the outer edges - Mandible base, with a small YELLOW SPOT on the upper side near the base or completely dark - Abdomen, T5 and T6, hairs, all WHITE - Wings, without any dark tinting - In comparison, smaller than the other 2 species (1)M. communis vs. M. pilleata, M. trinodis, and M. wheeleri - A very similar set of species Others - Short side of first flagellar segment shorter than or equal to the pedicel - Slightly smaller 9-11 mm (3) M. communis - Short side of first flagellar segment clearly longer than the pedicel - Slightly larger, 10-15mm (1)M. comptoides vs. M. trinodis vs. M. wheeleri M. comptoides - Head, labrum, ALL YELLOW - Mandible base, almost entirely yellow - Thorax, scutum, hair entirely pale - In comparison, larger than the others (1) M. trinodis - Head, labrum, yellow in the center and dark on the sides - Mandible base, completely dark or with a yellow patch - Thorax, scutum, hair entirely pale (1) M. wheeleri - Head, labrum, yellow in the center and dark on the sides - Mandible base, either completely dark or with small smudge of yellow - Thorax, scutum, hair greater than 50 percent dark, often with just a ruff of light colored hairs near the head, there hairs are not jet black, but more of a faded dusky brown-black so look closely as they often do not stand out (1)M. coreopsis vs. M. druriella vs. M. fumosa vs. M. nivea M. coreopsis - Head, labrum, entirely black, or with a very tiny smudge of yellow in the center - Head, antennae, the short side of flagellar segment one shorter or as long in length as the pedicel - Abdomen, tergites, hair color all white - Abdoment, tergites, rims, wide, transparent to very slightly milky - Head, mandible, base usually all black (1) M. druriella - Head, labrum, with YELLOW IN THE CENTER and black along the sides - Head, antennae, the short side of flagellar segment one clearly longer in length than the pedicel - Abdomen, some long dark hairs scattered above and below the white hair bands that run to the inside of the rims of T2 and T3, NOTE that these are not jet black hairs, but more of a gray, brown, smoky color, HOWEVER, MANY specimens have all white hair - Abdomen, tergite rims, dark brown to nearly opaque - Head, mandible, base, black (1) M. fumosa - Head, labrum, entirely black - Antennae, the short side of flagellar segment one clearly shorter in length than the pedicel - Abdomen, some long dark hairs scattered above and below the white hair bands that run to the inside of the rims of T2 and T3, NOTE that these are not jet black hairs, but more of a gray, brown, smoky color (1) M. nivea - Head, labrum, clearly with YELLOW IN THE CENTER and black along the sides - Head, antennae, the short side of flagellar segment one clearly shorter in length than the pedicel - Abdomen, tergites, all hairs bright white - Abdomen, tergite rims, light colored ,clear and clearly translucent - Head, mandible, base, almost always with a spot of yellow (1)M. denticulata vs. selected other species Others - In most the clypeus is entirely yellow or pale yellow or there is only a very narrow uniform dark border along the edge with the supraclypeus, this border is dark and only as wide as 1-3 clypeal pits (6) M. denticulata - Head, clypeus, upper border where it joins the supraclypeus is dark, the dark area varies from about half of the clypeus to very rarely just a narrow strip, the boundary is sharp but can be quite jagged - The lower portion of the clypeus is a creamy white color rather than the normal yellow or pale yellow (1)M. dentiventris vs. M. manipularis vs. M. subillata M. dentiventris - Abdomen, T2-4, completely COVERED IN BLACK HAIRS or only with a small amount of white on T2 on the sides of the hair bands - Leg, tibia, the rim of the basitibial plate, found at the base of the tibia, is evenly and clearly rounded - In comparison, larger than the other species (1) M. manipularis - Abdomen, T2-4, with prominent bands of white hair running parallel to the rim of the segments but set slightly back - Leg, tibia, the rim of the basitibial plate, found at the base of the tibia, is TRUNCATE, SQUARED OFF, or FLATTENED and definitely not round (1) M. subillata - Abdomen, T2-4, with prominent bands of white hair running parallel to the rim of the segments but set slightly back - Leg, tibia, the rim of the basitibial plate, found at the base of the tibia, is evenly and clearly rounded (1)M. druriella vs. M. boltoniae and M. fumosa M. boltoniae and M. fumosa - Head, labrum, usually entirely BROWN but at times with a smudy yellow spot in the center - Antennae, length of first flagellar segment almost exactly the same as the pedicel or slightly less - Thorax, scutum, with dusky and dark, but not jet black, hairs occupying over half of the segment (2) M. druriella - Head, labrum, usually with at least a spot of yellow in the upper center, YELLOW often quite extensive - Antennae, length of first flagellar segment clearly greater than the length of pedicel - Thorax, scutum, with no, or only a very small patch of dark hairs in the center of the segment (1)M. druriella vs. M. subillata - Another difficult pair to tell apart M. druriella - Abdomen, T2, in the center, the longitudinal width of the bare rim is usually about a bit greater to a bit less than the width of the white hair band behind it - In comparison the bare rims of T2-5 reflect less light, are darker brown, and are more opaque, but these differences very subtle (1) M. subillata - Abdomen, T2, in the center, the longitudinal width of the bare rim is usually much greater than the width of the white hair band behind it - In comparison, the bare rims of T2-5 are shinier, lighter browner, and a bit more translucent (1)M. illata vs. M. fumosa and M. boltoniae - A difficult and subtle group to differentiate M. boltoniae and M. fumosa - The center of the rim of T2 with pits with hairs in them going all the way to the rim, these pits are frequent and regular enough that they are obvious even though small, spacing is less than along the base of the segment averaging several pit diameters apart, but reasonably regular - In direct comparison, the surface of the mesepisternum, between the pits, tends to be readily reflect light with almost no fine dulling lines present (2) M. illata - The center of the rim of T2 with at least a short distance completely bare containing NO small pits with hairs in them - In direct comparison, the surface of the mesepisternum, between the pits, tends to be slightly dulled by numerous fine lines (1)M. manipularis and M. subillata vs. M. boltoniae, M. fumosa, M. illata, and M. wheeleri - Overall size, 8-10mm (4) - Overall size, 9.5-12mm (2)M. menuachus vs. M. tepaneca M. menuachus - Abdomen, T6, hair color, almost entirely WHITE - T4, behind the white transverse hair band, with scattered all white hairs - Head, labrum, yellow in the center but dark on the sides - In direct comparison, larger, 11-15mm (1) M. tepaneca - Abdomen, T6, hair color, almost entirely DARK brown to black - T4, behind the white transverse hair band, with scattered hairs all DARK brown or black - Head, labrum, all YELLOW - In direct comparison, smaller, 9-11mm (1)M. mitchelli vs. M. apicata M. apicata - Head, clypeus, PARTLY or sometimes COMPLETELY BLACK, if clypeus mostly yellow then there is a clear border of black along the boundary with the supraclypeus, clypeus densely pitted and dull throughout (1) M. mitchelli - Head, clypeus, YELLOW except for dark around tentorial pits, coarsely pitted except in the middle where it is largely unpitted and shiny (1)M. mitchelli vs. M. fimbriata - Abdomen, T2, apical hair band, hairs not reaching the edge in the middle third of the rim (1) - Abdomen, T2, apical hair band, hairs reaching the very edge across the entire rim (1)M. nivea vs. M. tepaneca vs. M. wheeleri M. nivea - Thorax, scutum and scutellum, all hair LIGHT - Abdomen, all hair WHITE (1) M. tepaneca - Thorax, scutum and scutellum, all hairs LIGHT - Abdomen, T5, hairs usually all or largely DARK brown or black - T2-4, behind the traverse band of dense white hairs, DARK hairs are usually found (1) M. wheeleri - Thorax, scutum and scutellum, on the rear part, the bulk of the hair on is a DARK to LIGHT BROWN - Abdomen, T5, hairs usually all or largely DARK to LIGHT brown or black - T2-4, behind the traverse band of dense white hairs, DARK to LIGHT brown hairs are usually found (1)M. subillata, M. manipularis, M. pilleata - Shortest length of 1st flagellar segment vs length of pedicel Equal to or less than (2) Greater than, even if just slightly (1)M. trinodis and M. dentiventris vs. M. boltoniae and M. fumosa - Larger, 10-13mm long - Thorax, hairs with an orangish-rust tint - Scutum, pit spacing, on center rear quarter, excluding the margin, about one-half a pit or less apart (2) - Smaller, 8-11mm long - Thorax, hairs weakly off-white - Scutum, pit spacing, on the center rear quarter, excluding margin, on average, much more than a pit apart (2)M. trinodis vs. M. dentiventris - Abdomen, T2 and T3, LACKING hair bands, or if with hair bands, then band is light or missing on T2, and band is at least partly dark on T3 - T4-T5, bands completely dark on - T2 and T3, tufts of hair on the sides, thick, long, and lighter colored than the hair bands and the rest of the hair on T3-T6 - Head, antennae, 1st flagellar segment is shorter than the pedicel (1) - Abdomen, T2 and T3, WITH complete, light colored hair bands - T2 and T3, tufts of hair on the sides are the same color as the hair bands and not noticeably long or thick - Head, antennae, 1st flagellar segment equal in length to pedicel (1)M. vernoniae vs. M. agilis, M. fumosa, and M. subillata Others - Longest hairs on the rear tibia are three-quarters or longer than the width of the tibia at its mid-point - Difficult to come up with a quantitative method of telling from M. agilis, but in general M. agilis has longer, denser, and more up upright hairs on the terga, the hairs throughout this species have a warm yellowish cast in contrast to the clear off-white cast to that of M. vernoniae, the thin rim of the clypeus of M. agilis tends toward an orange color while that of M. vernoniae is more towards dark brown - Told from M. fumosa and M. subillata by these species dark brown to black hairs which occur scattered throughout the transverse band of white hairs (3) M. vernoniae - In comparison this species has shorter hair on the rear legs - No hairs on the rear tibia are longer than the two-thirds the width of the middle of the tibia (1)M. wheeleri vs. M. trinodis M. trinodis - Thorax, overall hair color, often quite orangish - Scutum, rear half, excepting the extreme margin, pit spacing, less than one pit width apart (1) M. wheeleri - Thorax, overall hair color, generally off-white to yellow with patches towards the posterior of light brown hairs - Scutum, rear half, excepting the extreme margin, pit spacing, 1-2 pit widths apart (1)State or province where bee was collected IL (24) IN (24) KY (24) MS (23) NC (22) SC (22) VA (21) WI (21) GA (20) MD (20) MI (20) NJ (20) OH (20) WV (20) AL (19) DC (19) DE (19) FL (19) PA (19) TN (19) NY (16) Ontario (15) SD (12) MA (11) CT (10) RI (10) ME (9) NH (9) VT (9) New Brunswick (6) Nova Scotia (6) Quebec (5) Newfoundland and Labrador (3) Prince Edward Island (3)Subgenus Eumelissodes (18) Melissodes (4) Apomelissodes (3) Callimelissodes (2) Heliomelissodes (1)Thorax, scutum and scutellum, color of hair - Be sure to look at all angles as dark hair can look very light when viewed from the top rather than the side or rear All LIGHT (17) More than half of both plates covered in dark, edges likely outlined with light hairs, especially upper edge of scutum (15) Scutum mostly light with a small dark spot, scutellum may be light or may be dark in the center and outlined in light (11) All DARK (1)